Lichen watch
History of Irish Lichenology
Frenchman H. A. Weddell was the first to recognize lichen seashore zonation in 1875 when he defined three zones. Matilda Knowles (National Museum of Ireland) further defined this zonation in 1913 by defining zone colours and later associated lichen species with the zones. In 1929 she wrote ‘Lichens of Ireland – a History of Irish Lichenology’. This difficult to find paper of over 125 pages is available here for download: part 1 and part 2. (each part is read more
Why Lecanora zosterae seems rare
Lecanora zosterae plays tricks with the eyes, especially when found in abundance on the dead stems of the Sea Pink Armeria maritima. One moment you see it and just as quickly it dissolves leaving you struggling to catch a glimpse of it on the dried stems of a Sea Pink in your hand. Part of this enigma is explained by the thallus losing itself in the dried stems (immersed); part is explained by the similarly coloured apothecial discs. read more
New Flora Published
The aptly titled text ‘The Lichens of Great Britain and Ireland’ has been published (May 2009). This is the second edition; the last edition, published in 1992 was titled ‘The Lichen Flora of Great Britain and Ireland’. After much discussion the term ‘flora’ was dropped from this new edition. It is a much needed update due to the still growing advances in lichenology in the last 17 years. Over 385 new species have been added with many species names updated to reflect current taxonomic changes. read more
Caloplaca obamae
On March 9th, 2009 President Barack Obama lifted George Bush’s ban on using US taxpayers’ money to fund stem cell research. As a thank you to President Obama, Kerry Knudsen named a newly discovered lichen Caloplaca obamae. The new species was discovered by Kerry on Pleistocene soils on Santa Rosa Island. The name Caloplaca is derived from Greek meaning beautiful shield or patches. Ireland has about 40 Caloplaca species. read more
Fastest and Biggest yet Threatened
Ireland’s fastest growing lichen is the tree lungwort. Found in restricted areas of the West of Ireland it grows at a rate of 4 mm a year reaching sizes of 18 cm long by 3 cm wide. Its scientific name is Lobaria pulmonaria. Typically found on rowan, hazel and willow, its sensitivity to SO2 and shrinking habitat are placing it under threat in Ireland. Ireland needs to categorise this lichen as Nationally Scarce and take on International Responsibility for it. This specimen was photographed on a tree cut down in one of our National Parks.
Incineration Lowers Lichen Biodiversity
The practise of burning upland bogs and heathland to encourage the rapid regeneration of heather plays havoc with lichen biodiversity. Many species of the slow growing Cladonia group, such as Cladonia portentosa, that grow on and among mosses are wiped out. Lichen flora on boulders are also incinerated, as the photograph clearly shows. This specimen of Lecanora sulphurea probably took 60 years to grow, but met its demise recently. Photographed on June 19th, 2008 on one of Ireland’s heathlands.
Caloplaca thallincola
Caloplaca thallincola is the yellow lichen growing on the black Verrucaria maura in this photo. Its a typical rocky seashore lichen found in the ‘orange zone‘ about half way up a rocky sea shore.

